Abstract Transgender individuals are a gender minority group whose gender identity is different than their assigned sex at birth and, as a result, experience societal rejection, stigma, and prejudice. Healthy People (HP) 2020 recognizes transgender individuals as a population of interest due to health disparities between transgender and non-transgender (or, cisgender) individuals. Among health topics requiring special emphasis are mental health and mental illness, alcohol and illicit drug use, bullying among adolescents, health insurance coverage and usual source of care, and tobacco use. In particular, HP 2020 notes the need for to increase the number of population-based data systems used to monitor Healthy People 2020 objectives. In this application we address both these goals by proposing to collect, for the first time in the U.S., data from a probability sample of transgender adults. To date, no such data is available about the U.S. transgender population. A probability (nationally representative) sample of transgender individuals will help researchers provide unbiased data relevant to Healthy People and broader public health objectives. In addition, we will assess stressors and resilience factors that are implicated in causing negative health outcomes and health disparities between transgender and cisgender populations and study minority stress and resilience as mechanisms that explain health disparities. We propose to conduct a survey of about 1,000 transgender and 1,000 cisgender individuals representing the U.S. general population to allow comparison of the two populations to assess health disparities. We use an innovative sampling approach involving a 2-step procedure: In the first step, transgender and cisgender people are identified in a national probability sample of 350,000 individuals recruited using mobile and landline phone numbers (conducted by Gallup). In the second step, the identified transgender individuals and a random sample of cisgender heterosexual individuals will be assessed in a comprehensive online or mailed survey. This R01 application comes to complement a project that was started in 2015 with supplemental funding for a study that uses the same methodology to study lesbians, gay men, and bisexual men and women(LGB) adults (#HD078526), which allows for only one of two-years of required data collection and does not allow the inclusion of the cisgender comparison sample. Our data sharing plan calls for making available our data set to the public as soon as possible after data collection via publication in data archives.